1. Field of the Invention
This invention relates to additive and non-additive types of electrical interconnects for disk drive suspensions, and, more particularly, relates to improvements in the provision of electrical connections between conductive traces and a grounding metal in flexible circuit interconnects where the traces are spaced from a grounded metal layer by an intervening insulative layer, and no resin-based or solder-based electrical connection is used to effect the electrical connection, but a pin in mechanical contact with the outer surfaces is used to effect electrical connection.
2. Description of the Related Art
In the manufacture of disk drive suspensions an electrical interconnect is used to connect the slider with the device electronics. The electrical interconnect typically comprises a laminate of a first metal layer that is deposited in an additive assembly or etched in a subtractive assembly or otherwise formed into a plurality of conductive traces on an insulative layer of plastic such as polyimide film, and optionally a second metal layer of, for example, stainless steel or copper that is sufficient to provide a contact locus for electrical connection. The second metal layer or similar structure such as a pad can be used for connection of the interconnect to ground. To effect a grounding link, the trace conductors or a pad connected to the trace conductors is electrically connected to the second metal layer or similar structure that is grounded. This connection has been effected by filling an aperture that extends between the first and second metal layers through the insulative layer with a conductive resin, such as silver-filled epoxy, or solder supported or not by a stud within the aperture. The filled resin or solder is convenient and effective, but increasing awareness of chemical contamination of parts and environmental health hazards inherent in the use of the resins dictate finding a better system for making these interlayer electrical connections.